Amalgam carrier



Oct. 30, 1951 w. s. cRowELL AMALGAM CARRIER Filed April l0, 1946lmventor Ctttorneg 7' Patented Oct. 30, v1951 AMALGAM CARRIER Walter S.Crowell, Melrose Park, Pa., assignor to The S. S. White DentalManufacturing Company, a corporation of Pennsylvania Application April10, 1946, Serial No. 660,923

1 Claim. l

My invention relates to that class of dental implements that aregenerally known as amalgam carriers and are particularly adapted toinsert amalgam or other filling material into a tooth cavity to form astopping therefor, and is `especially directed to the means ofconnecting the plunger with the operating rod.

It has heretofore been proposed to construct amalgam carriers with theplunger and rod variously connected by a helically coiled wire or by anormally straight strand of Wire forced to bend in the curved barrel ofsaid carrier, which construction has proven to be unsatisfactory for thepurpose intended.

The principal objects of my invention are to provide an amalgam carrierhaving its barrel curved to direct its forward nozzle at a convenientlydirected angle to the axis of its handle, and having its plunger and rodmounted to reciprocate in the bore of said barrel and connected by asection of flexible shafting whose outer diameter is substantially lessthan the diameter of the barrel bore.

Other -objects of my invention are to provide an amalgam carrier havingits plunger and oper- `ating rod connected by a section of flexibleshafting comprising a plurality of oppositely coiled helical layers ofwires wound about a single strand of core wire.

Further objects of my invention are to provide an amalgam carrier with aremovable and replaceable terminal tip through which the snugly fittedplunger is arranged to slide.

My invention also includes the novel arrangement of construction inwhich the finger-hold collar connects the separately formed barrel andtubular handle and in which the plunger retracting spring, whichembraces the operating rod, is enclosed to exert -pressure tending toforce the thumb trigger button rearwardly, and effecting the consequentwithdrawal of the plunger in the nozzle.

Speciiically stated, the form of my invention as hereinafter moredefinitely described comprises an amalgam carrier having a tubularhandle terminating forwardly in a collar serving as a finger-hold andwhich forms the mounting for the forwardly extending barrel whichcarries the plunger in its laterally deected terminal region. Saidhandle is provided with a ferrule serving as a buffer for the adjustingnut which is adjustable on the reciprocatory operating rod to vary theaxial position of the plunger in the terminal nozzle and which is forcedinto engagement with said ferrule by the spring in the handle when thethumb trigger button is released to eiect withdrawal of said plunger.

My. invention also includes all of the various novel features ofconstruction and arrangement as hereinafter more definitely specied.

In the accompanying drawings, Figure 1 is a side elevational View of anamalgam carrier conveniently embodying my invention; Fig. 2 is a centralvertical longitudinal sectional View of the amalgam carrier shown inFig. 1, on a greatly enlarged scale showing the relatively associatedparts in their normal position; Fig. 3 is a central verticallongitudinal sectional view similar to Fig. 2 but showing the movableparts shifted to the forward limit of their movement; Fig. 4 is atransverse vertical sectional view taken on the line 4-4 in Fig. 2 on amuch greater enlarged scale; Fig. 5 is a transverse vertical sectionalview taken on the line 5-5 in Fig. 3 on the same scale as Fig. 4; andFig. 6 is a fragmentary side elevational View of the flexiblecouplingkshaft and plunger.

In said figures, the tubular handle I terminates forwardly in the collar2 which carries the forwardly extending barrel 3 having its forwardportion 4 curvedly deflected downwardly and ter-'- minating in theremovable and replaceable nozzle 5, which is removably engaged therewithby the screw threads 6.

Said handle I terminates rearwardly in a buffer ferrule 1 which isengaged therewith by the screw threads 8 and which has the peripheralknurling 9 by which it may be readily rotated, and the bore l0 throughwhich the stem II of the thumb trigger button I2 slidably extends.

The forward region of the thumb trigger button stem II is convenientlyprovided with the screw threaded bore I3 into which the screw threadedrearward terminal region of the axially reciprocatory operating rod I4is extended in threaded engagement therewith for axial adjustment.

Within the handle I and screw-threadedly embracing the rod I4 is theadjustable lock nut I5 between which and the collar 2 is disposed theplunger retracting spring I6 which is helically coiled about the rod I4'within the bore of said handle I, and which is arranged to be compressedby the forward movement of the thumb trigger button I2, as illustratedin Fig. 3, and which normally tends to force the adjusting nut I5 intoengagement with the buffer ferrule 1, las illustrated in Fig. 2.

The forward end portion of the rod I4 is flexible and includes a lengthof flexible shafting I1 of relatively reduced diameter extended throughthe curved region 4 of the barrel 3, and formed integral with thenon-ilexible portion of the rod I4 and the plunger I8 and flexiblyconnects themv together in a relatively definite axial relation.

The flexible shaft section Il of the operating rod I4 comprises an axialcore wire I9 and the coiled layers 20, 2| and 22 of wire alternatelylaid in relatively ioppsi't'e directions, asbestishowniin Fig. 6.

My invention is advantageous in that it provides a positive action ofthe plunger I8 by reason of its connection with the operatingrod nI4 bythe flexible shaft section I1 having the core wire I9 which maintainsafdefniteaxi'al length between the rod I4 and plunger f3 faiidtheoutercoils of said flexible shaft section provide faiplurality of roundedsurfaces serving'las `restricted 5 Number parting from the essentialfeatures of my invention as defined in the appended claim.

Having thus described my invention, I claim: An implement of the classdescribed, comprising a hollow handle having a forwardly extended barrelcurvedly deflected laterally and terminating in a nozzle region, aplunger mounted for axial 'in'ovementfin saidfnozz'le region, triggermeans t'inc'lud'ing'a stema-nd rod adjustably engaged in threadedrelation and arranged to force dsaid plunger outwardly, a lock-nutarranged to retain-said stem and rod in axially adjusted relation, asection of flexible shafting including an'axial"cere"wir-"e,fconriecting said rod and plunger, and'a springI'contained in said handle and tending -to withdraw said plunger intosaid nozzle region. 1

WALTER S. CROWELI... y

REFERENCES CITED The yfollowing `references fare of record inthe 'file"of Cthis patent:

UNITED r'S'I'A'IS PTETS Name Date Arthur Sept. 11, 1906 `Goodhugh v Oct.9, 19.06 .Holtz. r Sept. 25, 1923

